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The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

Coagulation factor VII is a vitamin K-dependent factor which is essential for hemostasis. It circulates in the blood as a zymogen which is later converted to an active form by factor IXa, factor Xa, factor XIIa, or thrombin by minor proteolysis. Upon activation of factor VII, a heavy chain with a catalytic domain and a light chain with 2 EGF-like domains are generated, and the two chains are held together by a disulfide bond. The presence of factor III and calcium ions further activates the coagulation cascade by converting factor IX to factor IXa and/or factor X to factor Xa. Alternative splicing of factor VII results in 2 transcripts. Defects in coagulation factor VII can cause coagulopathy. Coagulation factor VII initiates the extrinsic pathway of blood coagulation. Minor proteolysis converts factor VII to factor VIIa by factors Xa, XIIa, IXa, or thrombin. Factor VIIa also converts factor IX to factor IXa in the presence of tissue factor and calcium.

Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

PET117 is nuclear gene essential for the assembly of active cytochrome c oxidase in S. cerevisiae. Nevertheless the gene products are not subunits of the final assembled cytochrome c oxidase complex. PET117 is found in chromosome V proximate the HIS1 gene.

FK506 Binding Protein 5 (FKBP5) belongs to the immunophilin protein family, which has a role in immunoregulation and basic cellular processes involving protein folding and trafficking. FKBP5 is a cis-trans prolyl isomerase, which binds to the immunosuppressants FK506 and rapamycin. FKBP5 is an immunophilin protein with PPIase and co-chaperone activities. FKBP5 is assumed to mediate calcineurin inhibition. FKBP5 is a component of unligated steroid receptors heterocomplexes through interaction with heat-shock protein 90 (HSP90). In addition, FKBP5 interacts functionally with mature hetero-oligomeric progesterone receptor complexes along with the 90 kDa heat shock protein and P23 protein.

ERCC1 polypeptide is essential for nucleotide excision repair (NER) of damaged DNA and is homologous to Saccharomyces cerevisiae RAD10, which takes part in repair and mitotic intra-chromosomal recombination. NER mechanism includes dual incisions on both sides of the damage catalyzed by two nucleases. In mammalian cells XPG cleaves 3' of the DNA lesion while the ERCC1-XPF complex makes the 5' incision.

MMP-3 enzyme is also known as Stromelysin-1or as Transin-1 which hydrolyzes natural collagen at physiological pH and temperature. It dissolves the intervertebral nucleus pulposus and annulus fibrosus of Herniated Lumbar Intervertebral Disk . MMP-3 hydrolyzes components of the extracellular matrix like proteoglycan, laminin, fibronectin, gelatin and collagen types III, IV and IX. It also activates pro-MMP-9 and pro-MMP-8 and superactivates plasmin activated MMP-1. MMP-3 is secreted as a latent proenzyme and is activated by a variety of proteinases, e.g. plasmin, trypsin, chymotrypsin, cathepsin G or human neutrophil elastase. MMP-3 was found to be capable of activating the precursor of IL1-beta.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

SNTA1 is a member of the syntrophin gene family. SNTA1 is a peripheral membrane protein found linked with dystrophin and dystrophin-related proteins. Dystrophin is a large, rod-like cytoskeletal protein located at the inner surface of muscle fibers. Dystrophin is absent in Duchenne Muscular Dystrophy patients, however it is present in reduced amounts in Becker Muscular Dystrophy patients. Syntrophins are cytoplasmic peripheral membrane scaffold proteins and components of the dystrophin-associated protein complex. The N-terminal PDZ domain of SNTA1 interacts with the C-terminus of the pore-forming alpha subunit (SCN5A) of the cardiac sodium channel Nav1.5. In addition, SNTA1 associates cardiac sodium channels with the nitric oxide synthase-PMCA4b (plasma membrane Ca-ATPase subtype 4b) complex in cardiomyocytes. The SNTA1 gene is a predisposition locus for Long-QT syndrome (LQT) - an inherited disorder associated with sudden cardiac death from arrhythmia - and sudden infant death syndrome (SIDS). SNTA1 also associates with dystrophin and dystrophin-related proteins at the neuromuscular junction and modifies intracellular calcium ion levels in muscle tissue.

The acute phase plasma protein ORM1 synthesized by the liver mediates the interaction between blood cells and endothelial cells. In addition, together with haptoglobin and C reactive protein, ORM1 regulates the extravasation of the cells through infection and inflammation. Expression of ORM1 is induced by acute-phase stimulatory mediators such as bacterial lipopolysaccharides.

Heterogeneous Nuclear Ribonucleoprotein A/B (HNRNPAB) is a member of the subfamily of ubiquitously expressed heterogeneous nuclearribonucleoproteins (hnRNPs). The hnRNPs are produced by RNA polymerase II and are components of theheterogeneous nuclear RNA (hnRNA) complexes. They are linked with pre-mRNAs in the nucleus and seem to influence pre-mRNA processing and further aspects of mRNA metabolism and transport. Whereas all of the hnRNPsare present in the nucleus, some seem to shuttle between the nucleus and the cytoplasm. The hnRNP proteins have distinct nucleic acid binding properties. HNRNPAB, which binds to one of the components of the multiproteineditosome complex, has two repeats of quasi-RRM (RNA recognition motif) domains that bind to RNAs. Among the diseases associated with HNRNPAB are wells syndrome, and cystic fibrosis.

ATPaseTransporting Beta 1 (ATP1B1) is a part of the family of Na+/K+ and H+/K+ ATPases beta chain proteins, and the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an essential membrane protein accountable for establishing and maintaining the electrochemical gradients of Na and K ions over the plasma membrane. These gradients are vital for osmoregulation, for sodium-coupled transport of a range of organic and inorganic molecules, and for electrical excitability of muscle and nerve. ATP1B1is combined of 2 subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The beta subunit regulates the number of sodium pumps transported to the plasma membrane through assembly of alpha/beta heterodimers. ATP1B1 is a beta 1 subunit.

ARL4A is related Specifically to ARL6 and ARL7 and belongs to the ARF-like protein (ARL) subfamily of small GTPases. However, unlike ARFs, ARL4 does not activate the cholera toxin ADP-ribosyltranferase. ARL4A takes part in neurogenesis during embryonic development and somitogenesis in the early stages of adult spermatogenesis.

Mago-Nashi Homolog B (MAGOHB) is a member of the mago nashi family. MAGOHB involved in mRNA splicing and in the nonsense-mediated decay (NMD) pathway. MAGOHB interacts with RBM8A and is a part of the exon junction complex (EJC) containing NCBP1, NCBP2, RNPS1, RBM8A, SRRM1, NXF1, UPF3B, UPF2 and ALYREF/THOC4.

Mps one binder kinase activator-like 3 (MOBKL3) is a member of the MOB1/Phocein family and is phosphorylated on serine residues. MOBKL3 is usually linked with membranes but can be present in the cytosol, where it behaves as a protein complex. MOBKL3 is the major partner of the striatin family members, which are scaffolding proteins involved in signaling and trafficking.

FSCN1 is an actin-bundling protein that is responsible for rigidity to filopodial bundles to efficiently push the membrane forward during cytoskeleton remodeling and cell migration. FSCN1 takes part in the gathering of actin filament bundles present in microspikes, membrane ruffles, and stress fibers. FSCN1 is absent from most normal epithelia though is upregulated in multiple forms of human carcinoma, where its expression associates clinically with a poor prognosis. FSCN1 expression is abundantly found in neurons, glial cells, and endothelial cells.

Tumor-associated calcium signal transducer 2 (TACSTD2), is a member of to the EPCAM family. TACSTD2 is an intronless gene which encodes a carcinoma-associated antigen. TACSTD2 may act as a growth factor receptor and as a cell surface receptor that transduces calcium signals. Mutations of TACSTD2 have been associated with gelatinous drop-like corneal dystrophy.

STIP1 is an adaptor protein that mediates the functions of HSP70 & HSP90 in protein folding. STIP1 supports the transfer of proteins from HSP70 to HSP90 by binding together HSP90 and substrate-bound HSP70. STIP1 stimulates the ATPase activity of HSP70 and inhibits the ATPase activity of HSP90, suggesting that it regulates both the conformations and ATPase cycles of these chaperones. STIP1 genetic variations are involved in regulating corticosteroid response in asthmatic subjects with reduced lung function.

Canopy 3 homolog (CNPY3) is a 271 a.aToll-like receptor specific co-chaperone for HSP90B1. CNPY3 is necessitated for proper TLR folding, excluding that of TLR3, and so controls TLR exit from the endoplasmic reticulum. Therefore, CNPY3i s required for both innate and adaptive immune responses.

ATPaseTransporting Beta 3 (ATP1B3) is a member of the X(+)/potassium ATPases subunit beta family. ATP1B3 is the non-catalytic component of the active enzyme, which catalyzes the hydrolysis of ATP coupled with the exchange of Na+ and K+ ions across the plasma membrane. The beta subunit controls, by way of assembly of alpha/beta heterodimers, the quantity of sodium pumps transported to the plasma membrane. The precise role of the beta-3 subunit is unknown.

Since April 2012, cases of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) have been identified in various countries. Coronaviruses are the cause of the common cold, SARS (severe acute respiratory syndrome) and other severe illnesses with high mortality rates, all are classified into coronavirus family. MERS-CoV is a new type of SARS found in the coronavirus family causing severe pneumonia with sudden and serious respiratory illness with high mortality rates as well. Since January 27th 2015, the WHO has reported 956 human cases, including 351 deaths. More cases of the new coronavirus strain are expected. Like in other coronaviruses, large surface spike glycoprotein is a central structural protein of this virus; it is located above the virion surface to bind and enter into the target cell. Spike protein has 2 domains- S1 and S2. The S1 domain is responsible for cellular tropism and interaction with target cell, while the S2 domain is responsible for membrane fusion. The C-terminal of S1 domain contains a receptor binding domain, and is also a potential target for vaccine development and an antigen for diagnosis.

Calbindins are Ca-binding proteins belonging to the troponin C superfamily. CALB28K/Calbindin1/CALB1 (D28K/Spot35 protein or cholecalcin, rat 261 aa; mouse 261 aa; human 261-aa, chromosome 8q21.3-q22.1) was originally described as 27-kDA induced by vitamin D in the duodenum of chicken. In mammals, it is expressed in the kidney, pancreatic islets, and brain. In brain, its synthesis is independent of vitamin D. CABP28K contains 4 active and 2 inactive EF-hand Ca-binding domains. The gene for CABP28K is clustered in the same region as carbonic anhydrase. The neurons in the brains of patients with Huntington disease are CAB28K depleted. There are two types of CaBPs: the "trigger"- and the "buffer"-CaBPs. The conformation of "trigger" type CaBPs changes upon Ca2+ binding and exposes regions on protein that interact with target molecules, thus altering their activity. The buffer-type CABP are thought to control the intracellular calcium concentration. Calbindin D-28K is found predominantly in subpopulations of central and peripheral nervous system neurons, and in certain epithelial cells involved in Ca2+ transport such as distal tubular cells and cortical collecting tubules of the kidney, and in enteric neuroendocrine cells.